The remaining tickets for this year's World Cup in Qatar will be available on a first-come, first-served basis from next week, FIFA said on Wednesday.
About 1.8 million tickets were sold in the first two batches of sales, FIFA said, without saying how many are now available.
Qatar will host the first World Cup in the Middle East from November 21 to December 18 at eight stadiums in and around the capital, Doha.
The latest tickets will go on sale online from July 5 at 12pm Doha time (0900 GMT) until 12pm on August 16, FIFA said in a press release.
"Huge worldwide interest is anticipated in the new sales period," the world body said.
Officials said three million tickets are available in total, including those allocated to sponsors.
Last week, the World Cup's chief organiser Hassan Al-Thawadi said 1.2 million tickets had been sold so far.
FIFA president Gianni Infantino said there were five million ticket requests just for the final at the 80,000-seat Lusail stadium.